Tool joint and method of making



Feb. 11, 1941'. w H F 2,231,225

TOOL JOINT AND METHOD OF MAKING Fileci Feb. 26, 1938 IHHIiE TTTTJMIiI Haber? Sbhlumpf INV E NTOR ATTORNEY Patented Feb. 11, 1941 UNITED STATES 'roor. JOINT m mz-rnon or MAKING Robert W. Schlumpf, Houston, Tex, sssignorto Hughes Tool Company, llouston, Tex., a corf;

poration of Delaware Application February 26, 1938, Serial No. 192,743

Claims.

My invention relates to tool joints such as are employed in coupling together sections of drill stem in deep well drilling operations.

Tool joints are subjected to rough handling in 5 use and also have to undergo heavy strains which tend to distort them and impair their efiiciency. Due to the bursting strain upon a tool joint box when the pin is screwed therein with great force, the box member tends to split and expand. Furl0 ther, the blows delivered upon the box member when the pin member is stabbed into it in assembling the drill stem in the well tends to mutilate the sealing surface upon said box member and thus impair its sealing effect in use.

It is an object of the present invention to provide a tool joint wherein the end of the box member of the joint adjacent the pin member is particularly tough and hard thus making it strongly a. resistant to wear and distortion or deformation 2 I desire to increase the strength of the joint transversely so that it will not be distorted due to bursting strains upon the box member.

It is an object to provide a method of constructing the box member so that the end thereof subjected to wear and strain will have the grain or fiber thereof circumferentially about the joint and thus enable the box to resist a strain tending to expand the end thereof.

It is known that metals have directional physical properties dependent upon the degree of deformation'in hot and cold working. The elongated structure producedin the direction of mechanical deformation is known as fiber, and metals that have been suiiiciently worked to produce a definite fiber have lower ductile properties when stressed in a direction across the fiber than when stressed in the direction of the fiber. The physical properties obtained by testing perpendicular to the fiber are known as transverse properties, while those obtained when testing in the direction of the fiber are known as longitudinal properties.

A hollow cylinder, such as the femal or box end of a tool joint or drill collar, has a definite fiber paralleling the axis and is stressed transversely with respect to the fiber by forces existed 'when making up the pin in the box. We find failures resulting in boxes by splitting, which is a manifestation of low ductility, or inability to stretch sufiiciently when expanded, toprevent rupture along the fiber.

A hard shoulder formed at the wear end of the box by welding thereto a special alloy steel ring,

would have this transverse weakness, unless some method is devised to produce a circumferential rather than an axial fiber in the metal of the ring. I desire therefore to secure upon the box end of the joint, a portion having circumferential fiber which will materially increase the transverse ductility of the finished shoulder thereon.

In the drawing herewith, Fig. 1 is a perspective view illustrating a blank plate of steel with the fiber shown running in a direction transversely thereof.

Fig. 2 is an end elevation thereof showing the 10 plate bent into cylindrical form with its lateral edges welded together.

Fig. 3 is a perspective view illustrating the welding of a wear ring to the box end of a tool joint.

Fig. 4 is a side view partly in central longituis dinal section showing a finished fool joint box.

In carrying out my invention, I construct the bodies of the joint sections in the usual manner except that allowance is made in the box member for the addition thereto of a hardened end 20 section of special steel alloy. The grain or fiber in the tool joint body is longitudinally thereof,

as indicated by the sectioning thereof at i in the Fig. 1 plate and at 2 in Figs. 3 and 4. Before the box member is threaded, I secure a wear ring 2 integrally to the end thereof which is to contact with the pin member.

In forming this wear ring, I take a blank 3 of steel of the desired dimensions such as is indicated in Fig. 1. This plate has been worked in 30 the usual manner by rolling and the fiber thereof runs in one direction as indicated. This plate or blank is then bent into the form of a cylinder as shown in Fig. 2 with the grain in a circumferential direction and the meeting edges are butt- 86 welded as shown at 4. The seam where the welding takes place is then machined to provide a cylindrical sleeve of the proper dimensions with the grain thereof circumferentially about the tube.

The end of the tube I is then flash welded to the 40 end of the box member I of the tool joint in the manner indicated in Fig. 3. An electrode I is clamped to each of the parts to be welded and the meeting ends to the section 3 and t are welded.

when thus welded the tube I is sawed oif. or otherwise severed from the tool joint box I so as to leave a ring, shown at I in Flg. 4, integrally secured to the end of the box member. After this ring I is thus secured to the joint, the box member is machined to the proper dimensions, threaded and heat treated in the usual manner.

There is thus produced a box member upon the tool joint which has at its upper or pin-receiving end a portion 8 which is of special alloy steel 55 resistant to wear and mutilation in use and in which the grain or fiber. is circumferentially of the joint thus making it resistant to bursting or circumferential deformation.

What I claim as new is:

1. A tool joint box member having one end threaded to connect with a pin member, said box member having a fiber longitudinally thereof and a ring welded to said threaded end and having the fiber running circumferentially thereof.

2. A tool joint box member having the grain of the metal running longitudinally of said member in the body thereof, and an end portion having the grain running circumferentially about the same.

3. A tool joint including a pin section and a box section, a wear resisting end on said box member presented toward said pin section and having the grain in the metal thereof running circumferentially about the said end.

4. In the construction oi. a tool joint box section the steps of forging a tubular blank so that grain therein runs in a direction parallel with the axes, forming a tubular member of special alloy steel of the same transverse dimensions as said blank, welding the ends of said blank and said member together, cutting 01! the end of said member to leave a ring of said special alloy steel integral with said blank, then threading and heat treating said blank to form the finished section.

5. In the construction of a tool joint box member, the steps of forming a tubular blank of the proper dimensions with the grain thereof running longitudinally thereof, rolling and working a plate of the required width and of special alloy steel to cause the grain to run transversely thereof, bending said plate into tubular form so that the grain is transversely of the tube, uniting the edges thereof, welding said tube in end to end relation to said tubular blank, severing a short ring of said tube on a transverse plane spaced slightly from the weld so as to leave said ring integrally united to the tubular blank, then forming threaded sockets in the ends of said tubular blank.

ROBERT W. SCHLUMPF. 

